Weft stop motion for looms



3, 1968 M. BALLBE 3,396,757

WEFT STOP MOTION FOR LOOMS Filed March 10, 1966 I 2 Sheets-Sheet 1 INVE NTOR:

MARIA 1V0 BA LL55 lm M Aug. 13, 1968.

Filed March 10, 1966 M. BALLBE WEFT STOP MOTION FOR LOOMS 2 Sheets-Sheet 2 INVENTOR: MARIAIVO BALLBE United States Patent 3 Claims. (51. 139-370 ABSTRACT OF THE DISCLOSURE A weft feeler for use in a loom especially a rapier loom has an oscillating driving member actuated in timed relation with the loom operating mechanism and this member can be connected to a normally stationary but movably mounted operation control member through a trigger. The trigger is operably connected to a feeler which lies in the path of the moving weft thread on beatup. If the weft is present it engages the feeler and thereby so shifts the driving member that the trigger does not engage the normally stationary control member; but if there is no weft the feeler is not moved and the trigger establishes connection between the driving member and the control member to shift the latter and operate a switch to stop loom operation.

The principal object of this invention is to provide a sensitive weft stop motion for a loom which will stop the loom as soon as a weft failure is detected. The invention finds particular application to a rapier loom wherein the selvedge threads are crossed before the rapier has completely left the shed of warp threads.

According to this invention a weft stop motion for a loom comprises a driving member continuously oscillated in timed relationship with the loom cycle so that it makes one complete osciillation for each cycle of the loom bottom shaft, a normally stationary control member adapted when moved to actuate a switch controlling the operation of the loom, and a trigger connected to a feeler which is normally positioned in the path of a weft thread that has just been laid across the shed of warp threads as the weft thread is pressed forwardly on beat-up, the arrangement being such that if there is weft present, the trigger is moved to an inoperative position, but if there is no weft present, the trigger is allowed to connect the driving member to the control member to move the latter so as to actuate the switch.

Preferably, the mechanism for oscillating the driving member is also adapted to lift the feeler out of the shed immediately after the time in the cycle when the trigger can connect the driving member to the control member. It is also preferred to incorporate a cam in the mechanism for oscillating the driving member, the cam being fixed to a shaft driven at the same angular velocity as the loom bottom shaft.

One construction of a stop motion for use on a rapier loom will now be described by way of example of the invention, with reference to the accompanying drawings, in which:

FIGURE 1 is an end view of a weft detector mechanism, and

FIGURE 2 is a view similar to FIGURE 1, but with certain parts removed to show other parts.

The weft detector mechanism is supported on a bracket which carries the temple (not shown). The bracket 10 is slidable on the breast beamshown at 11and can be locked in any required position along the breast beam according to the width of fabric which is to be woven. The detector mechanism is on the outside of the temple and is adapted to feel the weft thread in the selvedge of 3,396,757 Patented Aug. 13, 1968 ice the fabric. In the particular loom for which the detector has been designed, a selvedge is produced which is separated from the body of the fabric by a short distance, and the weft threads extending across this space between the fabric and the selvedge are cut at or near the temple. Moreover, the selvedge warp threads are crossed in advance of the time at which the fabric warp threads are crossed to nip the weft thread as it leaves the rapier.

A driving member in the form of a lever 12 is pivoted on a peg 13 projecting from the bracket 10, and tension spring 14 is connected between a peg 15 extending from the lever 12 and a fixed anchor peg 16 on the bracket (see FIGURE 2). The spring 14 tends to turn the lever 12 in an anticlockwise direction as seen in the drawings. At its upper end, the lever 12 carries a pivoted shaft 17 which in turn carries a clamp 18 for a feeler wire 19. The clamp 18 permits adjustment of the feeler wire forwardly and rearwardly, and the rear end of the wire is bent downwardly as seen in FIGURE 1, so that its rear end normally occupies a position in the path of movement of the weft thread as it is being pushed forwardly by the reed on a beat-up, and in the selvedge threads.

A trigger 20 is fixed on the shaft 17 and is loaded into the position illustrated by a light tension spring 21 extending between the catch and the lever 12. When there is a weft thread present in the selvedge warp threads, the feeler 19 is pressed forwardly, so that it turns the shaft 17 in an anticlockwise direction, lifting the trigger 20 against the action of the spring 21.

A short shaft 22 is journalled in the bracket 10, and carries a control lever 23, the upper end of which is formed with an abutment 24, which is normally in the forward path of movement of the trigger 20. Of course, if the trigger is turned due to a detection of weft, it does not engage with the abutment 24, and consequently, the lever 23 remains stationary. A tension spring 25 is connected between the lever 23 and an arm 26 fixed to the fixed peg 13 and this spring normally holds the control lever 23 in the position shown where a tail 27 on the lever 23 engages with the anchor peg'16 (which thereby acts as a stop).

A substantially horizontal extension 28 of the tail 27 normally engages with the operating member of a microswitch 29 which is fixed to the bracket 10 and connected by leads 30 and 31 to the loom control circuit. This circuit is so arranged that the loom can be operated only so long as the switch 29 is closed by engagement of the extension 28 with its operating member. Once the extension 28 moves away from the switch, the latter opens and this causes the loom driving motor to be stopped and the brake to be applied.

The loom is provided with a shaft 32 extending across its width just to the rear of the breast beam, and driven by a chain device from the loom driving mechanism so that it rotates at the same angular velocity as the loom bottom shaft. This shaft 32 is used to operate a weft cutter as described in United States patent application Serial Number 544,726 filed April 25, 1966, for Weft Cutter for a Loom With a Stationary Weft Supply, and it provides a convenient means of operating the driving member 12 in timed relationship with the operation of the loom. A cam 33 is locked to the shaft 32 (the cam being adjustable relatively to the shaft for timing purposes) and a ball bearing 34 rotatable on a stub shaft 35 projecting from a lever 36 act as a follower for the cam. The lever 36 is pivoted on a peg 37 fixed in the bracket 10, and is loaded downwardly by a tension spring 38 anchored at one end to the lever 36 and at its other end to an outwardly directed end of a rod 39 fixed to and depending from the bracket 10.

At its rear end, the lever 36 is formed with a rod 40, the extremity of which is turned through so that it lies under a rod 41 fixed to the lever 12 and rotatable about the peg 13. Consequently, at each pick of the loom, the cam 33 lifts the lever 36 against the action of the spring 38, and the rod 40 lifts the rod 41 and turns the lever 12 clockwise. This always has the effect of lifting the feeler 19 upwardly and forwardly out of the selvedge and this is necessary because of the early crossing of the selvedge warp threads.

On the other hand, if not weft is present, the feeler 19 will not be turned and the trigger 20 is left in the position shown. As the lever 12 is turned by the operation of the cam 33, the trigger 20 catches the abutment 24, and turns the operating lever 23. This has the immediate effect of opening the switch 29 and stopping the loom.

It will be appreciated that the invention can be modifled in many details. In particular, the cam 33 could be replaced by a link mechanism operated from an eccentric on the loom bottom shaft if the shaft 32 were not provided.

I claim:

1. A weft stop mechanism for use in a loom comprising a driving member, means mounting said driving member for oscillation, driving means connected to said driving member for oscillating said driving member in timed relationship with the loom, a switch controlling the operation of the loom, a movably mounted normally stationary member operatively associated with said switch to cause said switch to stop the loom when said normally stationary member is moved, movably mounted feeler means normally positioned in the path of a newly inserted weft thread as it is being pushed forwardly by a reed on a beat-up, trigger means carried by said driving member and mounted for movement relative to said driving member by said feeler means between a first position where it stays if said feeler means is not moved due to absence of weft being beat-up and where it connects said driving member to said normally stationary member and 50 cause said switch to stop the loom and a second position where the weft being beat-up moves the feeler means to thereby move the trigger means so that it fails to establish a connection between said driving member and said normally stationary member, said trigger means being shifted to said second position solely by engagement with said weft being beat-up and independently of movement of said driving member.

2. A weft stop motion as claimed in claim 1, wherein said feeler means is a member carried by said driving member, said feeler member being so disposed that oscillation of said driving member lifts said feeler member out of the shed of the warp threads immediately after the instant at which said trigger means can connect said driving member to said normally stationary member.

3. A weft stop mechanism as claimed in claim 1, wherein said driving means comprises a cam fixed on a shaft roatating at the same angular velocity as the loom bottom shaft.

References Cited UNITED STATES PATENTS 2,638,942 5/1953 Hindle 139-370 2,819,737 1/1958 Opletal 139--37O 3,049,152 8/1962 Batty et al. 139-370 3,145,739 8/1964 Metzler 139-370 FOREIGN PATENTS 1,140,614 12/1960 France.

(1st addition to No. 74,514)

MERVIN STEIN, Primary Examiner.

J. KEE CHI, Assistant Examiner. 

